Since the density of water is 1 g /mL, hence there is 100
g of H2O. So total mass is:
m = 100 g + 5 g = 105 g
=> The heat of reaction can be calculated using the
formula:
δhrxn = m C ΔT
where m is mass, C is heap capacity and ΔT is change in
temperature = negative since there is a decrease
δhrxn = 105 g * 4.18 J/g°C * (-2.30°C)
δhrxn = -1,009.47 J
=> However this is still in units of J, so calculate
the number of moles of NaCl.
moles NaCl = 5 g / (58.44 g / mol)
moles NaCl = 0.0856 mol
=> So the heat of reaction per mole is:
δhrxn = -1,009.47 J / 0.0856 mol
δhrxn = -11,798.69 J/mol = -11.8 kJ/mol
Answer: We can think differently about maintaining social wellness during this time of social distancing by (consider the following)
Explanation: If you are in a crowded space, try to keep 6 feet of space between yourself and others at all times, and wear a cloth face covering. Cloth face coverings are especially important in times when physical distancing is difficult.
Pay attention to any physical guides, such as tape markings on floors or signs on walls, directing attendees to remain at least 6 feet apart from each other in lines or at other times. Allow other people 6 feet of space when you pass by them in both indoor and outdoor settings.
It’s D,the cold will bring cooler temperatures.....:)
pH of 0.40M triethylammonium chloride is 5.90.
<h3>What is pH?</h3>
A solution's acidity may be determined by looking at its pH, which is a measurement of hydrogen ion concentration. Pure water slightly separates into ions with roughly equal amounts of hydrogen and hydroxyl (OH) ions. [H+] is 107 for a neutral solution, or pH = 7.
<h3>Given : </h3>
Concentration of triethylammonium chloride = 0.40M
pH = ?
<h3>Solution: </h3>
(CH3CH2)3NHCl ------> (CH3CH2)3NH⁺ + Cl⁻
(CH3CH2)3NH⁺ will react with water to give H3O⁺ .
(CH3CH2)3N will have a Kb = 5.2 x 10 ^(-4)
Kw = Kb x Ka
=> Ka = Kw / Kb = 10^(-14) / 5.2 x 10 ^(-4)
=> Ka = 1.92 x 10^(-11)
so by the reaction we have ,
Ka = x²/(0.40 - x)
=> x = 1.2393 x 10 ^(-6)
now, pH = -log( [H3O⁺]) = - log ( 1.2393 x 10 ^(-6)) = 5.906
To learn more about pH :
brainly.com/question/15289741
#SPJ4
